Integrate changes 7819,7820 from vmsperl into mainline.

Add header for LIB$ prototypes (C. Berry)

Convert fwrite()s to sockets to write()s, since some socket stacks
don't take kindly to stdio.
Ignore "expected" SS$_NOLOGNAM when doing internal LNM lookups
(for often optional LNMs)
Correct a few typos
(C. Bailey)

p4raw-id: //depot/perl@8724